1. Field of the Invention
The present invention relates to keyboard connection configurations and electronic devices. One example of the present invention relates to ensuring a strong connection of a keyboard to a casing by providing multiple retaining portions at predetermined positions on the keyboard.
2. Description of the Related Art
In electronic devices such as personal computers, cellular phones, and PDAs (Personal Digital Assistant), etc., there is typically a keyboard (keyboard unit) having multiple operating keys. The keyboard is typically connected to a casing (see Japanese Patent No. 3218819).
With the electronic device described in Japanese Patent No. 3218819, an engagement pawl portion is provided on both edge portions of the keyboard, a hole portion and a pawl portion are formed in a casing, one of the pawl portions of the keyboard is inserted in the hole portion of the casing to engage this with the opening edge of the hole portion, and the other pawl portion of the keyboard is engaged with the pawl portion of the casing to connect the keyboard to the casing. With this arrangement, a backing plate for receiving the operating key at the time of an operating key being pressed is typically provided on the casing.
Note however, with the electronic device provided in Japanese Patent No. 3218819, only the pawl portions provided on both edge portions of the keyboard are engaged with the casing, whereby the keyboard is connected to the casing. Thus, if the backing plate is bent due to aging, temperature environment, or the like, the center of the keyboard floats upwards from the casing, and the sense of operation when pressing an operating key deteriorates, in some cases.
Particularly, in a case in which the backing plate is formed of a thin metal material such as aluminum or the like to reduce weight and thickness of the electronic device, bending of the backing plate readily occurs.
In order to prevent bending of the backing plate, for example, there is a method for fixing the center portion of the keyboard to the casing using screw-thread members, but this arrangement can create difficulties upon disassembly of the keyboard from the casing, and thus can lead to difficulty in maintenance.
Accordingly, there has been recognized a need to provide a keyboard connection configuration with a strong connection to the casing.